1. Field of the Invention
The present invention is directed to improvements in cleaning ionizing blowers of the type having a wire ionizing electrode supported within a gas stream for ionization of the stream. Accordingly, the general objects of the invention are to provide novel systems, methods, and apparatus of such character.
2. Description of the Related Art
Static-charge neutralizers commonly operate on high ionizing voltages applied to sharp-tipped electrodes or wire/filament electrodes. Ideally, operation of such a neutralizer should produce a moving air stream of electrically balanced quantities of positive and negative ions that can be directed toward a proximate object having an undesirable static electrical charge to be neutralized.
Corona discharge ionizers of the type noted above include ionizing blowers. Some examples of these include the following products that are or have been offered by Simco-Ion of 1750 North Loop Road, Alameda, Calif. 94502: minION2 Compact Ionizing Blower; Benchtop Blower Model 6432e; Ionizing Blower Model 6422e; Ionizing TargetBlower Model 6202e; Ionizing Blower Model 5822i; and μ Wire AeroBar® Ionizer Model 5710. At least some of these products are the subject of (1) U.S. Pat. No. 7,212,393, entitled “Air Ionization Module And Method”, and issued on May 1, 2007; and (2) U.S. Pat. No. 7,408, 759, entitled “Self-Cleaning Ionization System”, and issued on Aug. 5, 2008. These U.S. patents are hereby incorporated by reference in their entirety.
Ion generation efficiency of corona ionizers of the type discussed above is known to degrade over time due to the deleterious effects associated with the use of high voltage and high current densities present at electrode tips and wires. For example, corrosion, oxidization films, and/or particulate contamination accumulating on the electrode surface(s) are a direct consequence of high voltage corona discharge. Ion production is inversely related to the accumulation of such contaminant byproducts for a number of reasons including the fact that these byproducts insulate the electrode(s) formed of common materials. As ion production decreases, target object discharge times increase until the degraded electrodes cannot even be used as a practical matter. Also, contaminated electrodes are prone to produce ozone and nitrogen oxides which are unacceptable in some applications. Since there are presently no systems in which the electrode alone can be replaced, replacing degraded electrodes necessarily includes replacing other blower components that still operate effectively. This is unnecessarily wasteful and expensive. While the use of titanium or silicon electrodes may reduce electrode erosion/degradation as discussed above, the specialized electrodes are expensive, cannot be used in all applications, and even they degrade over time. Thus, replacement of eroded electrodes (sometimes in complex installations) remains a frequent and expensive maintenance requirement that cannot be avoided, only managed.
One effort to reduce the maintenance discussed above involves periodically cleaning the ionizing electrodes in ionizing blowers. A limitation of this approach is that normal ionization operation must be interrupted while emitter cleaning can take place. As a result, emitter cleaning is performed only periodically and relatively infrequently. Naturally, this means that the ionizing electrodes almost never operate at peak efficiency. Moreover, contaminant accumulations and/or oxidization films can and do develop to the point that they are difficult or impossible to clean with known frictional/physical methods/systems.
Accordingly, improvements in ionizing electrode longevity, cleanliness, maintenance and/or replacement continue to be desirable.